The combination of electric field with compartmentalized cell-free gene expression reactions creates a simple, label-free approach for controlling biomolecules in space and time, opening possibilities for hybrid biological systems with a bioelectronic interface based on minimal biological parts design. Free of biochemical regulation, we demonstrate protein synthesis oscillations by on/off switching of the electric field. In response to the field, ribosomes, RNA polymerases, and nascent RNA and proteins are depleted from the DNA region where gene expression occurres. Direct electric-field manipulation of gene expression reactions would simplify the design of biochemical networks by replacing complex biomolecular interactions with push-button operations.